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milkmania
02-02-2011, 03:00 PM
I know we've got some pretty handy guys around here, so I pose this question....

I've got a heat pump here and it's 19 degrees today, and I hesitate to switch over to "emergency" heat...

Which is most efficient?
1) running the "heat pump" setting for extended periods of time.
2) switching to emergency heat and running for less amount of time

currently, the heat pump setting is keep it on the low side of tolerable (just gotta put on socks, sleep pants, t-shirt, etc)

Or, should I switch to emergency heat and get nekked:confused:

I put a thermometer in the ductwork in the heater closet above the unit, and it's running about 77 degrees

NatesGr8
02-02-2011, 03:12 PM
I'd consider getting a space heater and plugging it in to whichever room you'll be in mostly. Heat pumps aren't that efficient at those cold temperatures and you're probably using quite a bit of electricity to run it. That being said, if you can tolerate the temperature when its running normally leave it at that.

flipper
02-02-2011, 03:16 PM
Slow and steady and find some company to keep you warm enough to sleep nekked. Other than that I gots nothin

milkmania
02-02-2011, 03:24 PM
Slow and steady and find some company to keep you warm enough to sleep nekked. Other than that I gots nothin

having to sleep with my feets out from under the covers already:headbang:

captain planet
02-02-2011, 03:28 PM
I know we've got some pretty handy guys around here, so I pose this question....

I've got a heat pump here and it's 19 degrees today, and I hesitate to switch over to "emergency" heat...

Which is most efficient?
1) running the "heat pump" setting for extended periods of time.
2) switching to emergency heat and running for less amount of time

currently, the heat pump setting is keep it on the low side of tolerable (just gotta put on socks, sleep pants, t-shirt, etc)

Or, should I switch to emergency heat and get nekked:confused:

I put a thermometer in the ductwork in the heater closet above the unit, and it's running about 77 degrees

I entered the world of electric heat with our new house this year. What a winter to dive into this. I'm a bit unfamiliar with the emergency setting. I'm assuming this setting just uses the coils to heat rather than the heat pump to heat? Odds are if you are at temperatures below 28 to 32, you are heating with the coils anyway because there isn't any heat to grasp from outside to heat. This is my understanding from my buddy that is in the heating and cooling business.

We just wear socks and sweatshirts at our house......and let the dog sleep in the bed at night for extra heat.

milkmania
02-02-2011, 03:29 PM
anybody see anything out of line here?

looks like cooler spring and fall weather uses less electricity
and the opposite for full summer and winter

:confused:

ski_king
02-02-2011, 03:31 PM
Mine is setup to switch from heat pump to gas when the outside temp gets below 38.

I have used it into the high 20's before and it seemed to be working hard.

Assuming your emergency setting kicks on electric resistance heaters to help out, thats what I would recommend.

I am not a HVAC contractor, but I stayed at a Holiday Inn Exress once.

captain planet
02-02-2011, 03:33 PM
anybody see anything out of line here?

looks like cooler spring and fall weather uses less electricity
and the opposite for full summer and winter

:confused:

What is the square footage of your house?

milkmania
02-02-2011, 03:34 PM
I entered the world of electric heat with our new house this year. What a winter to dive into this. I'm a bit unfamiliar with the emergency setting. I'm assuming this setting just uses the coils to heat rather than the heat pump to heat? Odds are if you are at temperatures below 28 to 32, you are heating with the coils anyway because there isn't any heat to grasp from outside to heat. This is my understanding from my buddy that is in the heating and cooling business.

We just wear socks and sweatshirts at our house......and let the dog sleep in the bed at night for extra heat.

my outside condenser/ fan is running right now.... it's 20 degrees.
when it freezes the fins, it goes into defrost mode.
rinse & repeat

My inside coils don't kick on until I switch to emergency heat.

so, effectively...right now blower fan on heater and fan on condenser are the only thing running.
you can really tell when I switch to emergency heat....hotter heat comes from the vents

milkmania
02-02-2011, 03:35 PM
What is the square footage of your house?
2,180 sqft heated

milkmania
02-02-2011, 03:38 PM
I just signed up to "average" my electric bills this month....
it averages $184.00 per month now

anybody know the pros or cons to this?
an $81.00 electric bill in October sure comes in handy.
and the $288.00 bill in January sucks donkey sacks!
it's gonna take me till spring to recover from Christmas at this rate

captain planet
02-02-2011, 03:43 PM
my outside condenser/ fan is running right now.... it's 20 degrees.
when it freezes the fins, it goes into defrost mode.
rinse & repeat

My inside coils don't kick on until I switch to emergency heat.

so, effectively...right now blower fan on heater and fan on condenser are the only thing running.
you can really tell when I switch to emergency heat....hotter heat comes from the vents

Again, I'm new to this whole electric heat pump thing. But I think to a certain degree your coils are assisting while you are defrosting. I hear my heat pump going in and out of 'defrost' mode, when I can hear it switching I get hotter heat from my vents for a while also, so I'm guessing it is getting assistance from the coils. I'll talk with my buddy tonight and confirm how it works.

I do know one thing for sure, my heat pump gets a lot of frost built up on the fins. When I wash the cars I go over and spray it down with water to melt the ice off of it.

According to a friend of mine that has taken some classes on how to conduct energy audits, your electric bill isn't outside the normal range for your square footage. I asked him the same question last week because my house seems cool. My electric bill is around $240 for 2010 sq. ft. and he said that was normal. He also suggested just raising the temp a couple degrees because heat pumps work at catching up to the temp you desire whereas gas stays ahead of it by a couple degrees due to the temps they put out at the registers.

captain planet
02-02-2011, 03:46 PM
I would be interested to hear from anyone else that has electric heat pumps. I guess $240 in the winter months for electric is better than $120 in electric and $300 in gas. I would still rather cook with gas than electric though. :(

milkmania
02-02-2011, 03:49 PM
Again, I'm new to this whole electric heat pump thing. But I think to a certain degree your coils are assisting while you are defrosting. I hear my heat pump going in and out of 'defrost' mode, when I can hear it switching I get hotter heat from my vents for a while also, so I'm guessing it is getting assistance from the coils. I'll talk with my buddy tonight and confirm how it works.

I do know one thing for sure, my heat pump gets a lot of frost built up on the fins. When I wash the cars I go over and spray it down with water to melt the ice off of it.

According to a friend of mine that has taken some classes on how to conduct energy audits, your electric bill isn't outside the normal range for your square footage. I asked him the same question last week because my house seems cool. My electric bill is around $240 for 2010 sq. ft. and he said that was normal. He also suggested just raising the temp a couple degrees because heat pumps work at catching up to the temp you desire whereas gas stays ahead of it by a couple degrees due to the temps they put out at the registers.

I'll give some more background on my setup....
home was built in 2000 by a local Vocational Technology Center with 2x6 walls, and the HVAC was installed by a certified instructor with his own business on the side.
He just basically claims the HVAC was "sized for the house"

I'm just trying to prevent "wasting" energy :)

milkmania
02-02-2011, 03:51 PM
I would be interested to hear from anyone else that has electric heat pumps. I guess $240 in the winter months for electric is better than $120 in electric and $300 in gas. I would still rather cook with gas than electric though. :(

not me....
my 3 egg omelets turn out perfect EVERYTIME at 5.5 on the dial 8p
Brown meat on 8
simmer on 2

I have no gas bill

I've trimmed my monthly expenses down to $450.00 to $600.00
only fluctuating because of electric usage
I'm talking about:
1) dishnetwork
2) 4 cell phones on AT&T
3) house phone/DSL
4) electric
5) water
6) limousine insurance (note: no payments for Oct., Nov., & Dec.....only pay 9 months out of 12 )

captain planet
02-02-2011, 03:53 PM
I'll give some more background on my setup....
home was built in 2000 by a local Vocational Technology Center with 2x6 walls, and the HVAC was installed by a certified instructor with his own business on the side.
He just basically claims the HVAC was "sized for the house"

I'm just trying to prevent "wasting" energy :)

IIRC from my conversations with my home builder buddy, if you have 2x6 walls you are better off with electric heat compared to my 2x4 set up built in 1978. I think you are fine, just raise the thermostat a little. Raising it by 2-4 degrees, you will see about a $10-$15 per month increase in your bill according to my source.

captain planet
02-02-2011, 03:54 PM
not me....
my 3 egg omelets turn out perfect EVERYTIME at 5.5 on the dial 8p
Brown meat on 8
simmer on 2

I have no gas bill

Along that same line, I would rather have a gas hot water tank than electric.

milkmania
02-02-2011, 03:59 PM
Along that same line, I would rather have a gas hot water tank than electric.


switched over from 4500 watt water heater to a 5500 watt 5 years ago....
at the same time, switched over to a half wagon wheel style exterior entry door, from a full glass

saw immediate savings on electric!

Craig
02-02-2011, 04:07 PM
I am not an HVAC technician but I do research on HVAC/thermal systems for a living.

You are running too cold.

When you try to run your heat pump at temperatures even approaching 32F the outdoor coil has to drop below freezing to collect heat, so you are going to collect ice. Collecting ice reduces efficiency in the outdoor coil and thus reduces the amount of heat you can move inside.

Cycling the defrost constantly is pretty hard on the compressor as well. They are very robust machines but I doubt you want to pay for a premature failure.

In general, you should switch to conventional methods of heat if you are going to drop below freezing temperatures for extended periods.

What is your 'emergency' heat? Gas? Electric baseboards/space heaters? Whatever it is, based on your electric bills, you need switch over.

captain planet
02-02-2011, 04:11 PM
I am not an HVAC technician but I do research on HVAC/thermal systems for a living.

You are running too cold.

When you try to run your heat pump at temperatures even approaching 32F the outdoor coil has to drop below freezing to collect heat, so you are going to collect ice. Collecting ice reduces efficiency in the outdoor coil and thus reduces the amount of heat you can move inside.

Cycling the defrost constantly is pretty hard on the compressor as well. They are very robust machines but I doubt you want to pay for a premature failure.

In general, you should switch to conventional methods of heat if you are going to drop below freezing temperatures for extended periods.
What is your 'emergency' heat? Gas? Electric baseboards/space heaters? Whatever it is, based on your electric bills, you need switch over.

How? Run on emergency assuming that runs the coils rather than the heat pump?

Craig
02-02-2011, 04:22 PM
How? Run on emergency assuming that runs the coils rather than the heat pump?

Yes, emergency should stop the signal to the heat pump and run only on your backup heat source (electric/gas furnace, baseboards, etc.).

The biggest thing to watch out for is freezing up your heat pump completely. If you are not collecting too much ice it is fine and it should help, so keep it in normal mode.

It should be wired so that the heat pump and your backup run together when in normal heat pump mode. Emergency turns off the heat pump. Some systems may only run one or the other.

EDIT: I just realized you are probably talking about auxiliary heat, not a secondary heat source. The aux heat is like a poorly designed electric furnace, so it will cost a lot of money. Same thoughts apply as above but I would hesitate a bit more before switching to axillary only.

milkmania
02-02-2011, 04:37 PM
upon closer inspection....
my Heat Pump Thermostat is an analog Heil unit
If I need heat, I slide it up... the more heat I demand will cause the blue AUX light to come on

say it's 70 in here, I want 72...it just heats up normally
say it's 70 in here, and I demand 82 to break the chill... I slide it up past 80 and the AUX kicks in...once temp hits 80ish, AUX light goes off.

but, if I switch to emergency heat, AUX blue light and EMER red light comes on
blue light will toggle on and off when I reach desired temp.

outside coils is not building up during this particular weather... perhaps low moisture in the air?
using total electric in this house.
There is a wall blue flame propane heater mounted on the wall, but only use it during power failure

captain planet
02-02-2011, 04:49 PM
upon closer inspection....
my Heat Pump Thermostat is an analog Heil unit
If I need heat, I slide it up... the more heat I demand will cause the blue AUX light to come on

say it's 70 in here, I want 72...it just heats up normally
say it's 70 in here, and I demand 82 to break the chill... I slide it up past 80 and the AUX kicks in...once temp hits 80ish, AUX light goes off.

but, if I switch to emergency heat, AUX blue light and EMER red light comes on
blue light will toggle on and off when I reach desired temp.

outside coils is not building up during this particular weather... perhaps low moisture in the air?
using total electric in this house.
There is a wall blue flame propane heater mounted on the wall, but only use it during power failure

Mine sure do.....:mad::(

Well, based on this it sounds like I don't have 'emergency' heat. So my unit will continue to toggle back and forth from defrost to running with my coils assisting? So complicated, maybe I'll just get gas hooked up in the house.

Craig
02-02-2011, 04:52 PM
Aux heat are resistive heaters in the duct that will come on a couple of situations.

1) Your heat pump is defrosting and blowing cold air in the house, the heat strips minimize this.
2) Your heat pump is having a hard time keeping up with the heating load of your house and needs some help.

It sounds like everything is working normally, if you don't have ice don't switch to strictly aux heat.

I initially assumed that you had a separate furnace....don't know why I thought that.....too much time in the cold today I guess...

Where do you live?

milkmania
02-02-2011, 04:53 PM
Mine sure do.....:mad::(

Well, based on this it sounds like I don't have 'emergency' heat. So my unit will continue to toggle back and forth from defrost to running with my coils assisting? So complicated, maybe I'll just get gas hooked up in the house.

my first year had total electrical outage in county.....
even the water plant was down....
no water, no electric
I installed propane back-up heat the next spring

Craig
02-02-2011, 04:56 PM
Mine sure do.....:mad::(

Well, based on this it sounds like I don't have 'emergency' heat. So my unit will continue to toggle back and forth from defrost to running with my coils assisting? So complicated, maybe I'll just get gas hooked up in the house.

Yeah, it will.

I am surprised you do not have a furnace living in Canton.

milkmania
02-02-2011, 05:00 PM
Aux heat are resistive heaters in the duct that will come on a couple of situations.

1) Your heat pump is defrosting and blowing cold air in the house, the heat strips minimize this.
2) Your heat pump is having a hard time keeping up with the heating load of your house and needs some help.

It sounds like everything is working normally, if you don't have ice don't switch to strictly aux heat.

I initially assumed that you had a separate furnace....don't know why I thought that.....too much time in the cold today I guess...

Where do you live?


it's a all in one package
southeast Oklahoma on Arkansas state line near Fort Smith, AR

I'm confident everything's working properly.... was just trying to see what was most efficient

Craig
02-02-2011, 05:15 PM
it's a all in one package
southeast Oklahoma on Arkansas state line near Fort Smith, AR

I'm confident everything's working properly.... was just trying to see what was most efficient

Ok, gotcha.

Stick with heat pump setting. Just use emergency when you start icing the outdoor coil over.

etduc
02-02-2011, 06:28 PM
Leave it in regular operation mode....
Now, the truth. Depends how your heatpump was installed. Defost cycle design/aux heat, will greatly affect discharge temp. Each manufacturer, does it a little differently. In an effort to reach government (i.e. -"THE MAN") requirements, manufactures only temper the discharge air slightly. So this can cause cool air "out the grills" during the winter. This can be modified, significantly by a qualified professional. Just because someone is in the business, doesn't mean they, know their business! NOTE: Discharge air should not hit your body, winter or summer.

Some t-stats don't have emergency heat (EMT) switch. I prefer tstats with switch. Raise you tstat temp setting up (manually), by 2 degrees(most stats) aux heat will come on. Sometimes, a good quality tstat (located correctly) has a big impact on comfort. I recommend Honeywell "TouchScreen 8000"

Defost cycles usually are run time based. If ice is building up on you outside unit, may want to adjusted the time setting. A running compressor, is a well oiled compressor. I have several heat pumps over 30 years old. If you insist, on turning off your compressor, the above t-stat can be installed with an outside sensor. It will turn off you heat pump, and go to em. heat for you. BUT your em. heat must be designed to handle you total heating load.

As to cost of operation.. it is slightly cheaper to stay in heat pump mode, at extreme weather temps. Slightly! Operational ($) advantages of heat pumps is above 32 degrees, no one disputes that. (Where we send most of our, heating hours.)

For those, who think heatpumps blow cold air(winter) my father keeps his house 76 degrees!

milkmania
02-02-2011, 06:39 PM
snip
good info :rockon:

now let me ask you this
the little dial pointer inside the thermostat housing....
it appears to be a dial on a rheostat of sorts. where should it be set?
I think it has something to do with cycles???

dunno:confused:

edit:
nevermind.... I think I found it

milkmania
02-02-2011, 06:45 PM
cool stuff, learned something today :rockon:
http://homerepair.about.com/od/heatingcoolingrepair/ss/adj_anticipator.htm

etduc
02-02-2011, 07:02 PM
good info :rockon:

now let me ask you this
the little dial pointer inside the thermostat housing....
it appears to be a dial on a rheostat of sorts. where should it be set?
I think it has something to do with cycles???

dunno:confused:

edit:
nevermind.... I think I found it

Somewhere on the manufacturer name plate, it will tell where the lever should be pointed. It does, make a difference. Don't go to far beyond recommendations, as you can over heat house, then under cool during the summer.

TayMC197
02-02-2011, 07:43 PM
I know we've got some pretty handy guys around here, so I pose this question....

I've got a heat pump here and it's 19 degrees today, and I hesitate to switch over to "emergency" heat...

Which is most efficient?
1) running the "heat pump" setting for extended periods of time.
2) switching to emergency heat and running for less amount of time

currently, the heat pump setting is keep it on the low side of tolerable (just gotta put on socks, sleep pants, t-shirt, etc)

Or, should I switch to emergency heat and get nekked:confused:

I put a thermometer in the ductwork in the heater closet above the unit, and it's running about 77 degrees


Having much HVAC experience, if your house temp is already tolerable, then running heat pump will be fine. If your house is freezing, bring it up to a controllable temp with emergency heat first then switch over. Having a freezing house+ freezing outside = froze up compressor

TayMC197
02-02-2011, 07:47 PM
Also electric heat cost much more to run than reverse cycle heat. Also if you are experience long periods of cold temps. turn your settings up when you are gone to keep the house temp a little warmer. No less than 60. 65 is prefered. Having to heat the house will kill more electricity than maintaining it.